what oil is good or best for DTI

[smirnoff sri-dti]

I have 2.2 DTi sri and wish to ask you pips what kind of oil are you using for your DTi ?

I got my vectra c about 2 months ago and last owner said he changed oil few thou miles ago with coma semi sent. oil
I have checked everywhere that dti should run on FULLY Synthetic oil
so I got From GSF shop 5 by 30 fully synthetic
but when I changed it few guys told me that i should never go from SEMI to FULLY
.
what do you pips think : is it OK to change from Semi to Fully oil ?
.
what oil do you use in yours ?

[Celes]

Started using 10w40 semi on our DTi and it's running better/quieter. Was on GM 5w30 before.

[Big Sig]

It would of had fully synth when it was new.

[smirnoff sri-dti]

is it tru ?
the Thicker the Oil --- More Harder engine works

[Celes]

is it tru ?
the Thicker the Oil --- More Harder engine works

I had 5w50 in the 3.0CDTi and the mpg was the same as with the 5w30 or the 5w40 I'm using now.

[Big Sig]

is it tru ?
the Thicker the Oil --- More Harder engine works

Yes the thicker the oil the more resistance it puts up but I doubt it's much. Not forgetting the viscosity changes with temperature.

[John LE]

Over the past 3 services i've tried 3 different oils and my latest change has been the best

Firstly I used castrol's recommended 0w-30 edge and while it was ok the engine seemed quite loud and the oil far too expensive (pretty sure I was nearly 70 quid for it)

Last year I switched to Mobil1 0w-40 supersynth and fuel economy was great but the engine got really noisy and there was a puff of blue smoke on start up. My theory was that as the oil was so thin when cold it was dropping past the valve stem seals as things cooled down. This resulted in the car consuming oil. The costing of the Mobil1 was alot cheaper at about 50 quid but the resulting problems made me decide to change again this year

This year I switched to Castrols magnetec 5-30 (recommended for vx/opel) and it's turned out to be a great decision. The engine is alot quieter and smoother, the fuel consumption is still good and best of all the blue smoke on start up has gone.

I bought mine from Asda and it was about £40 but B&Q have it on special offer at the moment

Hope that helps

[Adam8220]

i use the gm 5w-30 and quite happy with it although now and then i do get a puff of smoke at start up.

[eaglepva]

I use titan super synthetic 5w/30 from unipart about £29 for 6litre. Its recomended for vauxhalls and pretty cheap.

[cont1204]

My 2.2 DTi has Castrol Edge 5/40 in it at the moment, nice and quiet.